1. Field of the Invention
The present invention relates to a coolant gas guiding mechanism in a compressor.
2. Description of the Related Art
A conventional wobble plate type compressor is shown in FIG. 4 as having a housing 52 with a suction chamber 50, and a discharge chamber 51. The suction and discharge chambers 50, 51 are separately disposed with respect to each other. Cylinder bores 53 are formed in a cylinder block 54. A valve plate 55 has a suction port 55a formed therein. A suction plate 56 has a flapper type suction valve 56a formed therein. The valve plate 55 is disposed between the cylinder block 54 and the housing 52. The suction plate 56 is located adjacent to the valve plate 55.
A working chamber 59, is defined by a piston 58 and the cylinder bore 53. When the piston 58 moves leftward, pressure inside the working chamber 59 decreases. The suction valve 56a is elastically deformed to open the suction port 55a, in order to allow the coolant gas in the suction chamber 50 to be sucked in, via the suction port 55a, into the working chamber 59. When the piston 58 moves rightward, after the suction operation is completed, pressure in the working chamber 59 rises, so that the suction valve 56a closes the suction port 55a.
Thereafter, when pressure in the working chamber 59 rises to, or above a predetermined level, the discharge valve 57a elastically deforms, and causes the discharge port 55b to open, via the discharge valve 57a, in order to discharge the compressed coolant gas from the working chamber 59, into the discharge chamber 51.
The suction valve 56a is designed to elastically regulate the opening of the suction port 55a as a function of the change in the suction pressure of the coolant gas. This design requires that the pressure of the coolant gas, in the suction chamber 50, be raised above that in the working chamber 59, in order to cause the suction valve 56a to be elastically deformed and to open the suction port 55a. Consequently, the opening response of the suction valve 56a is delayed with respect to the movement of the piston 58.
Furthermore, lubricant oil is mixed with the coolant gas, and collects on the suction valve 56a. Therefore, when the suction valve 56a elastically deforms to open the suction port 55a, oil might cause the suction valve 56a to adhere to the suction port 55a, thus adversely affecting the suction response.
Even when the suction valve 56a is opened, the suction response of the flapper type valve, which is elastically deformable, and which acts as suction resistance against the coolant gas to be sucked, is decreased by the design problem of the flipper type valve. Therefore, the decrease in the suction response results in a corresponding decrease of the amount of the coolant gas sucked into the working chamber 59, and an increase of the pressure loss in the compressor.
The coolant gas compressed in the working chamber 59 is discharged into the discharge chamber 51 at high temperature. Thus, the internal temperature of the discharge chamber 51 is also raised. In the conventional compressor, the suction chamber 50 and the discharge chamber 51 are adjacently located. The coolant gas introduced into the suction chamber 50, from an external coolant gas circuit, will expand its volume, due to heat transmitted from the discharge chamber 51 to the suction chamber 50. Therefore, the density of the coolant gas is caused to decrease, prior to letting it into the working chamber 59. This decrease results in density results in a decrease of the compressed volume in the working chamber, and in an increase of the pressure loss in the compressor.
Further, the elastic deformation of the flapper type valve is repeated and generates vibration. Corresponding pulsation is generated in the pressure within the suction chamber 50, and generates noise.